Two autopsied gastric cancer cases of rare drug-induced pneumonia associated with nivolumab plus S-1 and oxaliplatin: a case report.

Background: Drug-induced pneumonia, especially immune-related adverse events, can sometimes be fatal, and it is crucial to seize the signs for early treatment. A clinical trial (ATTRACTION-4) reported no cases of grade 4 or 5 pneumonia or interstitial lung disease associated with nivolumab plus S-1 and oxaliplatin. However, we encountered two cases of fatal pneumonia induced by this regimen. Case Description: The two patients were in their 70s, male and diagnosed gastric cancer with peritoneal dissemination. The patient of case 1 underwent surgery and adjuvant chemotherapy nine years before. The patient of case 2 was diagnosed unresectable 6 months before and chemo naïve. Both patients received nivolumab plus S-1 and oxaliplatin for the dissemination. The onset of both cases occurred after the fifth dose of the regimen, and the responses to corticosteroids were transient and limited. Computed tomography showed bilateral consolidation and ground-glass opacities, seemingly similar to an organizing pneumonia pattern. Acute and organizing stages of diffuse alveolar damage were detected histopathologically. Despite showing notable antitumor effects, both patients had indications of interstitial pneumonitis before admission, such as elevation of C-reactive protein (CRP) and Krebs von den Lungen-6 (KL-6) levels and slight lung opacity or respiratory symptoms approximately 10 days before admission. Conclusions: Patients undergoing nivolumab plus S-1 and oxaliplatin should be closely followed up with imaging, evaluation of symptom including oxygen saturation, and serological marker analysis such as lactate dehydrogenase, CRP, and KL-6. Early detection of pneumonia leads to adequate cessation of chemotherapy and early treatment, and this can prevent severe adverse events.

COVID-19 Vaccine-Associated Lymphadenopathy Mimicking Regrowth of Axillary Lymph Node Metastasis of Lung Adenocarcinoma.

We encountered a woman with re-enlarged axillary lymph nodes during a computed tomography (CT) scan for surveillance of lung adenocarcinoma with axillary lymph node metastasis at the initial diagnosis that had shrunk with standard chemotherapy. We first suspected cancer recurrence and considered a change in the chemotherapeutic regimen. However, after careful history taking regarding the timing of her Coronavirus Disease 2019 (COVID-19) vaccination, and subsequent careful, close follow-up, radiological shrinkage suggested a strictly benign cause. Especially in lung cancer with a medical history of axillary lymph node involvement, cliniciansshould be aware that vaccine-associated lymphadenopathy can mimic cancer recurrence and sometimesprompt serious misjudgment regarding a current treatment course and strategy.

[A Case of Long-Term Survival after Para-Aortic Lymph Node Recurrence Following the Curative Resection of Gastric Cancer Treated Using Multimodality Therapy Including Salvage Surgery].

This case was observed in a man in his 70s. Although symptomatic treatment was performed for epigastralgia, endoscopic examination revealed a type 3 tumor on the fornix of the stomach to the lesser curvature of the body just above the esophagogastric junction, and the patient was diagnosed with moderately differentiated tubular adenocarcinoma(cT4bN3aM0, cStage ⅣA). As esophageal and diaphragmatic invasion was suspected based on CT findings, S-1 plus CDDP was started as preoperative chemotherapy. Although the primary lesion and lymph node metastasis decreased in size, chemotherapy was discontinued after one course due to stenosis symptoms, and total gastrectomy and D2 dissection were performed. Postoperative adjuvant chemotherapy with S-1 was started. However, 6 months after starting the treatment, para-aortic lymph node recurrence was observed, and the treatment strategy was changed to weekly PTX. After 5 courses of weekly PTX, the lymph nodes continued to increase in size, and chemotherapy was discontinued per the patient's request. The patient was followed up with CT and PET-CT; however, no new recurrent lesions were found in other sites for approximately 1 year. Therefore, para-aortic lymph node dissection was performed as the salvage surgery. Pathological findings showed that gastric cancer metastasis was present in 1 swollen lymph node only, as confirmed by PET. At present, 6 years have passed since the first operation, and there has been no recurrence. In general, para-aortic lymph node metastasis is considered to result in poor prognosis in gastric cancer. However, in the absence of other noncurative factors, a good prognosis may be obtained with combined therapeutic modalities.